Method of production of the stable selenium-comprising pharmaceutical composition with a high selenium level

Abstract

The present disclosure relates to the new method of producing of the stable selenium-comprising pharmaceutical compositions with a high selenium level based on the mixing of nitric acid with therapeutically effective amounts of at least two active ingredients selected from the groups consisting of 2,2-dichlorocarboxylic acids, selenium-containing compound. As a selenium-containing compound the aqueous solution of selenious acid in the amount of no more than 20%, preferably 0.5-10.0%, is used. The group of 2,2-dichlorocarboxylic acids consists 2,2-dichloropropionic acid and their homologes The chemical process is carried out by adding of the concentrated nitric acid in amount of 1.0-5.0% into 2,2-dichlorocarboxylic acid purity of at least 98.5% and completing the redox-interaction under the isothermal conditions at a temperature not higher than 70° C., preferably at 20-30° C., and then an aqueous solution of the selenious acid in an amount of not more than 20.0% (and the other components if it is necessary) is added to form the result pharmaceutical product solution. The product can also contain additional 5-20% of dimethylsulfoxide. The claimed pharmaceutical product is useful for the treating of benign, viral, premalignant, and malignant non-metastasizing skin lesions, of dysplastic lesions of visible mucous coats, fungous and other skin diseases.

The invention is claimed as follows: 
     
       1. A method of preparing a stable pharmaceutical selenium-containing composition useful for treatment of skin diseases and comprising therapeutically effective amounts of at least two active ingredients selected from the group consisting of: alpha, alpha-dichlorocarboxylic acids, a selenium-containing compound, and a combination thereof, wherein the selenium-containing compound is selenious acid comprising:
 adding nitric acid into an alpha, alpha-dichloropropionic acid; 
 completing the redox-interaction under isothermal conditions at a temperature not higher than 70° C.; and 
 adding an aqueous solution of the selenious acid in an amount of not more than 20.0% to form the resultant pharmaceutical product solution. 
 
     
     
       2. The method of preparing a stable pharmaceutical selenium-containing composition of  claim 1 , wherein alpha, alpha-dichlorocarboxylic acid is 2,2-dichloropropionic acid. 
     
     
       3. The method of preparing a stable pharmaceutical selenium-containing composition of  claim 1 , wherein alpha, alpha-dichlorocarboxylic acid is dichloroacetic acid. 
     
     
       4. The method of preparing a stable pharmaceutical selenium-containing composition of  claim 1 , wherein the composition comprises 1-3% nitric acid. 
     
     
       5. The method of preparing a stable pharmaceutical selenium-containing composition of  claim 1 , wherein the composition comprises 0.5-10.0% selenious acid. 
     
     
       6. The method of preparing a stable pharmaceutical selenium-containing composition of  claim 1 , wherein the chemical interaction between alpha, alpha-dichlorocarboxylic acid and nitric acid is carried out at temperature of 20-30° C.